BirdingInSpain

Griffon Vultures and Bonelli’s Eagles

Hunched up and scowling like old crones on their narrow, guano-carpeted ledges small numbers of Griffon Vultures watch the acrobatics of the Bonelli’s Eagle couple with ill-concealed envy, letting out derisory hisses and scornful squawks. There’s no love lost between these two species; the eagles look down on these cumbersome carrion-feeders with disdain, and the vultures in turn eye the eagles with wary distrust.

Griffon Vultures in a snow storm

That has always been the nature of their relationship, although the dynamics of eagle-vulture interactions have recently taken on a new turn: currently embarked on a roller-coaster recovery from an all-time population low in the 1970’s and 80’s Griffon Vultures are proving to be unwelcome rock mates in the places where they coincide with Bonelli’s Eagles. The latter have become the unsuspecting victims of the vultures’ recent success story in that, ever the opportunist, the Griffon Vultures have started occupying Bonelli’s Eagle nests. Rather than pretending to build their own nests, which at the best of times could be greatly improved by copying the layout of a half-finished game of Chinese Straws, some Griffon Vultures have discovered that it’s much easier to gang up and oust the Bonelli’s Eagles from theirs, to then claim ownership of what must feel like the equivalent of a stately home.

Bonelli’s Eagle

To their everlasting credit the eagles are no pushover; their aerial prowess, power and speed, and their aggressive nature mean that they are well-equipped to put up a good fight. However, in the end the eagles succumb to the overpowering odds stacked against them by the number game and must retreat; perhaps to better prepare the defence of the nests that are still left to them.

Hunched up and scowling like old crones on their narrow, guano-carpeted ledges small numbers of Griffon Vultures watch the acrobatics of the Bonelli’s Eagle couple with ill-concealed envy, letting out derisory hisses and scornful squawks.